Rotator

ABSTRACT

The invention relates to a rotator ( 10 ) for jib-carried tools ( 1 ), for example tree working units, wherein the rotator ( 10 ) includes a stator ( 20 ) and a rotor ( 30 ), wherein the rotator ( 10 ) is connected to a tip ( 2 ) of the jib or arm ( 3 ) and to the tool ( 1 ). The rotator ( 10 ) has or includes in its surroundings means ( 70, 71 ) for determining the relative position of rotation between rotor ( 30 ) and stator ( 20 ). The means for determining the relative position of rotation comprises a pulse emitter ( 70 ) and a number of pulse generating elements ( 71 ), such as grooves or teeth. Limitation of the angle through which the rotator ( 10 ) can turn and control of the direction of rotation prevents, for instance, hoses and/or cables ( 7 ) from twisting or rotating away from their respective connections, while enhancing the extent to which automation can be achieved at the same time.

The present invention relates to a rotator for co-action withjib-carried tools in accordance with the preamble of claim 1.

One serious problem experienced with rotators for co-action with toolscarried on the ends of crane arms or jibs for instance, resides in theability to orientate hoses and possibly also cables in a rational mannerin respect of the driver of the vehicle. The driver must constantly beon his/her guard with regard to the choice of tool rotation, so as toavoid hose breakages. Externally disposed hose loops are vulnerable todamage and consequently a discrete or protected hose orientation isdesirable.

One object of the present invention is to provide a rotator, which willsignificantly simplify the work required from the driver of the vehicleand that will also enable a high degree of automatisation to beachieved. This object is fulfilled by virtue of the invention having thecharacteristic features set forth in the claims.

The following advantages are examples of the many advantages that areafforded by the present invention.

The invention eliminates hose breakages and cable breakages as a resultof wrong rotation of a tool, and also enables enhancement of automationso that the work of the driver will be simplified.

The inventive arrangement also affords both technical and economicaladvantages.

The invention will now be described in more detail with reference to anexemplifying embodiment thereof and also with reference to theaccompanying drawings, in which

FIG. 1 is a schematic side view of a so-called single-grip harvestingunit connected to a working arm or jib through the medium of aninventive rotator;

FIG. 2 is a vertically sectioned view of the rotator;

FIG. 3 is a sectional view of the rotator taken on the line III-III inFIG. 2; and

FIG. 4 is a sectional view of the rotator taken on the line IV-IV inFIG. 2.

FIG. 1 illustrates a tool in the form of a so-calledsingle-grip-harvesting unit 1 which is suspended from the tip 2 of amachine-carried jib/crane arm 3 through the medium of a rotator 10. Therotator 10 is suspended from a joint 4 or, e.g., from a swing damperthat allows the tool 1 to swing relative to the tip of the jib/crane arm3. The rotator 10 enables the tool 1 to be rotated relative to the tip 2of the jib. Hydraulic medium (oil) is supplied to the rotator 10 and tothe tool 1 through hoses 5. The connection of the hoses 5 to avehicle-carried source of hydraulic medium is not shown in the figure.

As will be seen from FIGS. 2-4, the rotator 10 includes a stator 20 anda rotor 30. The stator 20 includes an upper stator wall 21, a statorring 22 and a lower stator wall 23.

The upper stator wall 21 includes two attachment lugs 24 for attachmentof the rotator 10 to the jib/arm 3.

The rotor 30 is mounted in the stator 20 and is rotatable relative tothe stator 20 through the medium of two radial bearings 31,32 and oneaxial bearing 33. The illustrated rotator 10 is of the so-called wingtype, wherewith spring-biased wings 34 on the rotor 30 define, togetherwith the inner surface 24 of the stator and the outer surface 35 of therotor, those working chambers 36,37 required for rotation of therotator. The rotator has a multi-rotational and reversible rotationalcapacity.

In the case of the illustrated embodiment, the supply of hydraulicmedium to the rotator is effected by coupling hydraulic hoses 5 toconnection points on the upper stator wall 21, these connection pointscommunicating with the working chambers 36,37 of the rotator via anumber of channels (not shown) disposed in the stator wall 21. Althoughonly two channels 27,28 are indicated in FIG. 3, it will be understood,of course, that further channels that lead to the working chambers areincluded.

Mounted at the upper end of the rotor 30 is a swivel coupling/swiveldevice 40 which enables hydraulic medium delivered to the rotator 10(for instance via the hoses 5) to communicate with the tool 1. Hydraulicmedium is transferred to a longitudinally extending channel 41 in therotor 30 and to a longitudinally extending channel 42 in said rotor 30,via said swivel coupling. The channels 41 and 42 communicate with thetool 1, via hoses 6, so as to obtain the necessary supply of hydraulicmedium. The hoses 6 obtain a highly discrete and protected orientationin relation to the tool 1, whilst following the rotational movement ofthe tool at the same time.

When the tool 1 requires an electric power supply or has communicationsrequirements in the form of signal transmission or data transmission,the rotor 30 may include a through-passing transit hole, for instance acentre hole 45, through which the necessary electric cables and/orsignal cables 7 can pass. In this regard, the upper stator wall 21includes an opening 50 through which said cables can be drawn throughthe rotator. Further holes or channels 46 can be provided in the rotor30 when necessary, for desired media transits or the like.

The rotator includes a number of seals 51-55 for preventing mediumleakages.

The lower shaft end 38 of the rotor carries a non-rotatable clampingring 60 which, in turn, carries the tool 1 so that rotational movementof the rotator will be transferred to said tool.

In the illustrated embodiment, the rotor 30 carries a so-called pulseemitter 70 which communicates with, e.g., a computer unit or processor(not shown) on the tool 1. The pulse emitter 70 of the illustratedembodiment is connected to the rotor 30 via the clamping ring 60 whichaccompanies the rotational movement of the rotor 30 and also therotational movement of the tool 1. The lower stator wall 23 includes anumber of grooves 71 which give rise to pulses from the pulse emitter 70so as to enable the rotational position or twisting of the rotor 30relative to the stator 20 to be mapped and monitored continuously.

Thus, according to the invention, the relative rotational positionbetween rotor 30 and stator 20 can be determined with the aid ofrotation indicating means 70,71. It is therewith possible to limit theangle through which the rotor rotates in both directions from a desiredor chosen starting position/neutral position, so as to restrictrotational movement or twisting of, e.g., one or more connection cables7 for signal transmission, the transmission of electric power, or thelike. For example, the rotational ability of the rotor may be limited toabout one revolution in either direction from a neutral startingposition of the cable with respect to rotation or twisting of the cable.

When wishing to transmit the signals from the pulse emitter 70 to thevehicle or to the base machine, the pulse emitter is convenientlydisposed at the stator or in its surroundings and the grooves or toothedelements are disposed at the rotor or its rotation-accompanyingsurroundings.

It will be understood that it lies within the scope of the invention toexchange the pulse emitter and indicators co-acting therewith for otheralternative devices that are able to determine the relative position ofrotation between rotor and stator.

It will also be understood that the orientation or drawing of the hosesand, when applicable, cables may be varied within the scope ofinvention. This has been exemplified by broken lines in FIG. 1. Whendesiring less discrete and protected hose orientation, pressure mediumhoses 5′ for rotator operation may be connected to the stator 20, whileconnecting pressure medium hoses 6′ for tool operation directly to thetool 1 without passing the rotator 10. The rotator requires no swivelcoupling 40 in this latter case.

The rotator swivel coupling 40 may also be excluded when the pressuremedium hoses for tool operation are disposed through a transit holeextending longitudinally through the rotor 30, in the same way as thecable or cables 7.

As indicated in broken lines in FIG. 1, any signalling cable or electriccable 7′ required may be placed externally.

It will be understood that the rotator drive principle and structuraldesign may be varied widely within the scope of the present invention,and that the aforesaid wing drive may, for instance, be replaced by manyother types of rotational drives. The drive medium used may, of course,also be varied.

A central feature of the invention resides in monitoring the rotationalposition of the rotator and limiting its rotation. This enables hosesand cables to be drawn, orientated, in a highly beneficial manner. Thedanger of hoses and cables subjected to torsion being twisted orwrenched away from their respective connections is also eliminated. Theability to monitor said rotational position promotes the possibility ofsignificant automation.

The invention also enables the rotator to be monitored for undesirablerotational changes, so-called drifting, which when necessary can beeliminated by actively pressurising the working chambers of the rotatorin an appropriate manner. The inventive arrangement is also able to forexample actively control the braking sequence of the rotator.

Other variations are possible with regard to the connection of therotator to the jib/arm and the tool. For example, the rotator may bemodified structurally so that the rotor 30 is connected to the tip ofthe jib while the stator 20 is connected to the tool.

Instead of connecting the rotation indicating elements 70, 71 directlyto the rotator, it lies within the scope of the invention to arrangesaid elements in the surroundings of the rotator, for instance if thisis considered more suitable from a construction aspect.

As will be understood, limitation of the angle through which the rotatorturns may be excluded when it is only desired to continuously map ordetermine the rotational/twisting position of the rotator.

The inventive arrangement can also be modified, of course, by exchangingthe illustrated and described components for functionally equivalentcomponents.

Thus, the invention is not restricted to the illustrated and describedembodiment thereof, since modifications and variations can be madewithin the scope of the accompanying claims.

1. A rotator for jib-carried tools, for example tree working units,wherein the rotator (10) is hydraulically driven and includes a stator(20) and a rotor (30), and wherein said rotator (10) is connected to atip (2) of the jib or arm (3) via a link arrangement and to said tool(1), characterised in that the rotator (10) or its surroundings includesmeans (70, 71) for determimng the relative position of rotation betweenrotor (30) and stator (20) making it possible to limit the rotation ofthe rotor (30) and to enable a high degree of automatisation.
 2. Arotator according to claim 1, characterised in that the means fordetermining the relative position of rotation include a pulse emitter(70) and a number of pulse generating elements (71), such as grooves orteeth for instance.
 3. A rotator according to claim 2, characterised inthat the rotor (30) carries the pulse emitter (70) and that the stator(20) carries the pulse generating elements (71).
 4. A rotator accordingto claim 2, characterized in that the stator (20) carries the pulseemitter (70) and that the rotor (30) carries the pulse generatingelements (71).
 5. A rotator according to claim 1, characterised in thatthe supply (5) of pressure medium to the rotator is effected through themedium of connection points in the stator (20).
 6. A rotator accordingto claim 1, characterised in that the supply of pressure medium to thetool (1) is effected through the medium of a swivel coupling (40) andthrough the medium of channels (41, 42) in the rotor (30).
 7. A rotatoraccording to claim 1, characterised in that the supply of pressuremedium to the tool (1) is effected through the medium of at least onetransit hole extending longitudinally through the rotor (30).
 8. Arotator according to claim 1, characterised in that the supply ofelectric power and/or the supply of signals to the tool is effectedthrough the medium of at least one transit hole (45) extendinglongitudinally through the rotor (30).
 9. A method pertaining to arotator for jib-carried tools, for example tree working units, whereinthe rotator (10) is hydraulically driven and includes a stator (20) anda rotor (30), and wherein said rotator (10) is connected to a tip (2) ofthe jib or arm (3) via a link arrangement and to said tool (1),characterised by determining the relative position of rotation betweenrotor (30) and stator (20) with the aid of rotational positionindicating means (70, 71), limiting the angle through which the rotator(10) rotates in either direction from a starting position in order tolimit the extent to which pressure medium connection hoses present areable to twist and/or to limit the extent to which connection cables (7)for signals, date transmission, electric power supply, or the like, areable to twist and to enable a high degree of automatisation.
 10. Arotator according to claim 2, characterised in that the supply (5) ofpressure medium to the rotator is effected through the medium ofconnection points in the stator (20).
 11. A rotator according to claim3, characterised in that the supply (5) of pressure medium to therotator is effected through the medium of connection points in thestator (20).
 12. A rotator according to claim 4, characterised in thatthe supply (5) of pressure medium to the rotator is effected through themedium of connection points in the stator (20).
 13. A rotator accordingto claim 2, characterised in that the supply of pressure medium to thetool (1) is effected through the medium of a swivel coupling (40) andthrough the medium of channels (41, 42) in the rotor (30).
 14. A rotatoraccording to claim 3, characterised in that the supply of pressuremedium to the tool (1) is effected through the medium of a swivelcoupling (40) and through the medium of channels (41, 42) in the rotor(30).
 15. A rotator according to claim 4, characterised in that thesupply of pressure medium to the tool (1) is effected through the mediumof a swivel coupling (40) and through the medium of channels (41, 42) inthe rotor (30).
 16. A rotator according to claim 2, characterised inthat the supply of pressure medium to the tool (1) is effected throughthe medium of at least one transit hole extending longitudinally throughthe rotor (30).
 17. A rotator according to claim 3, characterised inthat the supply of pressure medium to the tool (1) is effected throughthe medium of at least one transit hole extending longitudinally throughthe rotor (30).
 18. A rotator according to claim 4, characterised inthat the supply of pressure medium to the tool (1) is effected throughthe medium of at least one transit hole extending longitudinally throughthe rotor (30).
 19. A rotator according to claim 2, characterised inthat the supply of electric power and/or the supply of signals to thetool is effected through the medium of at least one transit hole (45)extending longitudinally through the rotor (30).
 20. A rotator accordingto claim 3, characterised in that the supply of electric power and/orthe supply of signals to the tool is effected through the medium of atleast one transit hole (45) extending longitudinally through the rotor(30).